Automatic scraper control for rotogravure-printing presses



a, s. PRITCHARD. AUTOMATIC SCRAPER CONTROL FOR ROTOGRAVURE PRINTINGPRESSES.

, APPLICATION.FILED MAY29,1917. 1,362,638, 7 Patented Dec. 21, 1920.

n" 'l "i I II II I'll V. 1/ avwemtoi c. G. PRITCHARUQ AUTOMATIC SCRAPERCONTROL FORROTOGRAVURE PRINTING PRESSES.

APPUCATION FILE D M-AY29,'1917. 1,362,638, Patented Dec. 21, 1920.

2 -SHEETS-SHEET 2.

f a v %14 attozwz 'fr A T S G G. IPMTCHARD, 0F WARREN, OHIO, ASSIGNOR TOTHE HARRIS AUTOMATIC PRESS COMPANY, OF CLEVELAND, OHIO, A CORPQRATION OFOHIO.

AUT@MQ TIC SGRAPER CONTROL FOR ROTOGRAVUREJPRINTING- PRESSES.

Specification of Letters Patent.

Z PatentedDec. 21, 3920.

Application filed May 29, 1917. Serial no. 171,613.

To all whom it may concern: j

Be it known that ll, CARL Gr. PRITOHARD, a citizen of the United States,and a resident of Warren, in the county of Trumbull and State of @hio,have invented certain new and useful improvements in Automatic eration,either by throwing off the impression, or by disconnecting the press asa whole from the driving source of power. In printing-presses of thistype the printing operation is performed by a copper plate or shellsuitably secured to the form cyllnder or tngraved, such etched orengraved ortions 'being adapted to contaln the mk, while the smoothportions of the plate are free from ink. The ink is fed to the formcylinder in relatively large quantities from the ink fountain, and asharp scraper knlfe is arranged tangentially to the clrcular etchedplate and used to remove all surplus ink from the outermost'surfaces of.the plate. The edge of the knife is also arranged parallel to the axisof rotation of the form cylinder and the surplus ink falls back into thefountain as the cylinder is rotated. lln presses of this type, it isnecessary to employ devices to lift the scraper knife from the surfaceof the copper plate upon" the stoppage of the printing operation, lestthe sharp edge. of the knife cut into and ruin the etched surface of thecopper plate by any reverse movement of the press, thereby rendering theplate useless for further printing. I

The objects of my invention are, amon other things, to provide a simpleand e fective automatic scraper control mechanisrn, which may beactuated simultaneously either with the throwing-off of the impressionor with the stoppage of the press, controlled either by the operator orautomatically by a sheet detector device and I tripping mechanism whichoperate upon the outer surface of which is etchedthe failure of the feedof a sheet to the press. i 4

.i attain this result. by the mechanism shown in the accompanyingdrawings in which- Figure 1 is a side elevation of my improved controlshowing so much of a rotary press as isnecessary to illustrate myinvention;

Fig. 2 is a plan view of a part of the press shown in Fig. 1;

Fig. 3 is an end view partly in cross-section, of the tripping mechanismshown in Figs. 1 and 2.

Fig. 4i is a side elevation of a modified form of my invention the samebeing shown in connection with the clutch throw-off of the ress;

Fig. 5 is a plan view, similar to Fig. 2, only taken of the modifiedform of my invention shown in Fig. 4:; and

Fig. 6 is'an end view, partly in crosssection of the tripping mechanismshown in Figs. 4 and 5.

Similar numerals referredto similar parts throughout the severalfigures.

Referring more particularly to the embodiment of my invention shown inFigs.

1, 2V and 3, the frame 7 supports the bearings for the plate cylinder 8,carrying the etched copper plate 9, and the impression 7 1e gears whosepitch-diameter coincides i with the periphery of the respectivecylinders, These gears intermesh and form the driving mechanism tosecure the proper rotation for the cylinders. The power is derived fromthe belt 13 passing around the pulley 14 on the shaft 15 journaled inthe frame 7; the 'shaft 15 carrles the pinion 16 which intermeshes withthe pinion 17 mounted on the shaft 12. Since these are common forms ofprinting-press construction and are well-known in the art, they are. notshown in'detail in the drawings.

The shaft 11 carr ing theplate cylinder 8 is mounted at botli ends inthe eccentric bearings 18, one of which has the arm19 projecting-on theoutside of the frame 7 as shown more particularly inrFi'gs. land 2.

50 'plate 9, and simultaneously therewith the the lever 20 beingjournaled to the outer.

The toggle levers 'iand 21 connect the outer end of the arm 19 to theframe 7,

impression, or to manually operate the impression throw-off and scrapercontrol. The shaft 25 is held in the position shown in Fig. 1 bythelat'ch 29 secured to the rockshaft 30 journaled in the bracket 31inthe frame 7, which latch 29 engages a notch 32 in the sleeve 33mounted on the shaft 25 as this roll is rotated by shown in detail in-Fig. 2. Secured to the frame 7 is the horizontal ink fountain vat 34 tocontain the ink to be applied to the plate 9 b the inking roll 35 asfieing in contact with the outer surface of the plate. Mounted on therock-shaf t 36 which is journaled in the frame '7 is the hub 37 of thescraperknife 38 which preferably is removably secured to the hub 31 byset screws (not shown). "The edge of the knife 38 normally bears on theouter surface of the plate 9, as shown in Figs. 1 and 2, through theactionfof' 'the gravity weight 39 secured to the outer end of the arm 40mounted on the sleeve 41 aflixed to the rock-shaft 36 outside the frame7 as shown in Fig. 2. The sleeve 41 has also sesecured to the sleeve 33,when the parts are Fig. 1. When the in the position shown in rod 43 isshifted toward the left, either through the lifting of the hand-lever 27or through the counter-clock-wise rotation of the shaft 25 by therelease of the latch '29, the edge of the scra er knife 38 is reniovedfrom contact with t eoute'r isii'r'fiices of'the toggle levers 20 and 21will be broken in the direction of the arrow shown in Fig. 1 through the.movement of the link 23 to throw off the impression.

Preferably this latch 29 would be released automatical y through tripmechanism on I the feeder, as shown more particularly in Fig. 3. InFigs. 1, 2 and 3, 46 designates thefeed table, and in Fig. 3, 47indicates the sheet of stock that is being fed to the press. Extendingtransversely, above the feed table 46 and journaled-to projections inthe frame 7 is the shaft 48 which carries the arm 49 connected by therod 50 pivoted to.

the pin 51 ongthe impresison cylinder shaft 1.2, so as to impart totheshaft 48 an oscillat-' ing movement during the operation of the press.52, 52'designate two grooved collars rigidlysecured to the shaft 48 andadjacent each grooved collar 52 is the disk 53 of substantially the samediameter as the collars 52, which disk is afiixed to the inner end ofthe tubular shaft 54 which is loosely sleeved on, and incloses a portionof the shaft 48, as shown in Fig. 3. The shaft 54 carries the arm 55 theouter end of which bears against the arm 56 mounted on theh'lock 57aflixed to the rock-shaft 30. 58 indicates the triplever pivoted at 59between the parallel sides of the grooved collars 52, so that its largerthe disk 53, are formed cut-outs 62 and 63 respectively. Ordinarily thetooth 61 rests against, or is in proximity to, the periphery of the disk53; it can engage with the cutout 62 of the collars 52 only when it canfall into the cut-out 63 of the disk 53. When this occurs, the disk 53and its shaft 54, which are normally at rest,,are locked to and turnwith the oscillatin shaft 48. The entrance of this tooth 61 into lockingengagement with the disk 53 will occur upon the failure or interruptionin the feed supply. Where the stock 47 is in proper position, as shownin Figs. 1 and 3, the curved longer arm of the trip-lever 58 will engagetherewith and will be supportedthereby so as to be prevented.from'loweri'ng into the opening 60, and from turning sufficiently tointerlock with the disk 53. If the stock 47 should, at any time, beinterrupted or absent, the lon er arm of the trip-lever 58 will fall ofits own weight into the opening 60, thereby causing the tooth 61 tointerlock with the cut-out 63 in the-disk 53. Thus the tubular shaft 54will be caused to oscillate with the shaft 48 so as to cause the arm 55to lift the arm 56 to release the latch 29 engagin the notch 32 in thesleeve 33 on the sha t 25. Through the movement of this hereindescribedmechanism, the spring-impelled shaft 25. is partially rotated in acounter-clockwise direction to swing the eccentric bearings 18 to throwoff the impression by separating the plate cylinder 8 from theimpression cylinder 10, and at the same time lift the edge of the scraer knife 38 from the outer surface of the p ate 9, all-controlled by thestock.

It is also apparent that the o erator, by moving the hand-lever 27 tothe eft in Fig. 1 and lifting the latch29 may simultaneously throw offthe impression and lift the till lessees scraper knife 38 from the plate9 by a single movement so that the two throwing-d operations worktogether and in unison. In practice, it is essential that the scraperknife 38'be restored to its contact positionwitli the plate 9 on thecylinder 8 at least a half revolution of the cylinder 8 in advance ofthe restoration of the printing relation of the cylinders 8 and 10, sothat the outer surface of the plate 9 may be cleaned of surplus inkbefore beginningto contact with the sheet l7 cylinder with thedisconnecting or the power th upon the stoppage of the press.

l Vhen the clutch members are reset upon the starting of the press, theedge. of'the scraper knife is restored to contact with plat-e cylinder,or the ln'iife may be placed in operative position on the cylinderbefore the press is started.

Referring to Figs. 1 and 5, 6d designates the frame of the press inwhich the form cylinder carrying the etched plate 88, and the impressioncylinder 87 are mounted on the shafts 88and 89 respectively journaled inthe frame 64:, the two cylinders 65 and 07 forming a printing couple.The two cylinders are geared together as has been hereinbefore describedwith reference to the cylinders 8 and 10. Power is transmitted to theimpression cylinder 87, from the loose and fixed pulleys and '71 to thedriving shaft 7 2 journaled in the frame 0% as shown. 7 3 is thepositive clutch member slidably secured to the shaft 7 2 and is adaptedto engage the clutch member 7 at mounted onthe shaft 7 5; the clutch 74:carries the miter-=- gear 76 which engages with the miter-gear 7 7mounted on the impression cylinder shaft 69 to securethecounter-clockwise rotation of the impression cylinder 6?. 78 is astubshaft secured to the frame (it and 79 is a sleeve jcurnaled on theshaft 78 which sleeve 79 has a depending arm 80 carrying at its lowerend the clutch yoke 81 adapted to engage, and coact with, the annulargroove 82 formed in the clutch member 78 as shown in Fig. i. Extendingupwardly from the sleeve 79 is the arm 88 having the rod 84; pivotallysecured to its outer end.

The rod 86lertends forwardly of the press and near outer end carries thelug on under oi is adapted to engage and coact 88 secured to the outerend of arm 87 mounted on the transverse shaft 88 journaled in the'frame8d. The shaft 88 carries the hub 89 upon which the scraper knife 90 isremovably secured in the same manner as the knife 38. 91 is the inkfountain from which ink is supplied to the plate 66 through therotatable ink roller 92. The shaft 88 carries the arm 93 from which thegravity weights 9d are suspended to normally maintain the edge of theknife 90 in contact with the plate 66. When the rod 84 is moved to theleft either by the lifting of the hand-lever 95 or by the action of theautomatic sheet-detector device hereafter to be described, the knife 90will be thrown off from the plate 86 simultaneously with thedisconnecting of the clutch members 73'and 74 which stops the press.Preferably the two throw-offs will be controlled and actu ated by theautomatic sheet-detector device, shown more particularly in 1F ig, 6.

lin Figs. 4., 5 and 6, 96 indicates the feed table and in Fig. 6, 97designates the sheet of stock that is being fed to the press. Er:-tending transversely above thp feed-table 96 and journaled toprojections in the frame 04: is the rock-shaft 98 which carries the arm99 connected by the rod 100 which is pivoted to the pin 101 in theimpression cylinder shaft 09, so as to impart to the shaft 98 .an

oscillating movement during the operation of the press. 102', 102designate two grooved collars rigidly secured to the shaft 98, andadjacent each grooved collar 102 is the disk 103 of substantially thesame-dian'ieter as the collars 102 which disk 103 is secured to theinner end of the tubular shaft 1041 which is loosely sleeved on, andincloses a portion of, the shaft 98-, as shown in Fig. 0. The shaft 10%has rigidly secured to itsouter .end' the collar 105 upon which ismounted the arm 106 which, in turn, is con nected to the hand-lever 95by the link 107. 108 designates the trip-lever pivoted at 109 betweenthe parallel sides of the rooved collars. 109; so that its longer anddieavier arm is held from falling into the opening 110 out in the top ofthe feed-table 98 by the interposition of the stock 97 as shown in land0. At'the opposite end the triplever 108 is T-shaped to form the tooth111, and in the peripheries of the sides of the collars 102, and also inthe periphery of the dial; 108 are formed cut-outs 112 and 113respectively. Ordinarily the tooth 111 rests against, or in proximityto. the periphery of disk 108; it can engage with the cutout .112 of thecollars 102 only when it can fall into the cutout 113 of the disk 103.When this occurs the disk 108 with its shaft 104, which are normally atrest, are locked to and turn with the oscillating shaft The entrance ofthis tooth 111 into locking engagement with the disk 108 w occur uponthe failure or interruption one fee l supplyw When the stckw97 is inproper engage therewith and will be supported thereby, so as to beprevented from lowering into the opening 110, and from turningsufficiently to interlock with the disk 103. If

. the stock 97 should, at any time, beinterrupted or absent, the longerarm of the trip-lever 108 willfall of itsown weight into the opening110, thereby causing the tooth 111 to interlock with the cut-out 113 inthe disk 103. Thus the tubular shaft 104 will be caused to oscillatewith the shaft 98 so as to cause the arm 106 to lift the handlever 95through the link 107 'to simultaneously disconnect the clutch members 73and 74 on the one hand, and to throw the scraper knife 90 off thesurface of the plate" 66 on the other. When the clutch is reset theknife 90 is automatically brought at once into contactwith the plate 66as soon as the press starts, or the knife may be returned to thecylinder before starting by raising the rod 84 out of engagement withthe' pin 86.

The foregoing constructions both j embody the principles of my inventionas a plied to a two-cylinder'press, but it is o vious that my inventionis applicable to other forms of printing-presses, and that othercombinations and modgs of operation may be made, the foregoing beingsufiicient to disclose the underlying principles and advantagesinvolved.

I claim as my invention:

1. In a printing-press having a plurality of cooperating printingmembers, inking devices for one of said members,'means for removingsurplus ink from said last-mentioned member, means for tripping saidprinting members, and'means directly act'uated bysaid tripping means forplacing said ink-removing means in inoperative position simultaneouslywith the stoppage of the printing operation,- said last means allowingthe ink-removing means to be moved into operative position before theprinting relation of said p ting members is resumed.

2. In a printing-press having a plurality of cooperating printingmembers, inking devices for one of said members, means for removingsurplus ink from said last-mentioned member, means for tripping saidprinting members, and automatic means di-- rectly actuated by saidtripping means for placing said ink-removing means in inoperativeposition simultaneously with the stoppage of the printing operation,said last means allowing the ink-removing means,

to be moved into operative position before the printing relation of saidprinting members is resumed.

, 3. In a printing-press having a plurality of cooperating printingmembers, inking devices for one of said members, means for removingsurplus ink from said last-mentioned member, means for tripping saidprinting members, and automatic means directly actuated by said trippingmeans and controlled by the stock, for placing said ink-removing meansin inbperative position simultaneously with the stoppage of the printingoperation, said last means allowing the ink-removing means to be movedinto operative position before the printing relation of said printingmembers is resumed. I

4. In a printing-press having a plurality of cooperating printingmembers, inking devices for one of said members, means for removingsurplus ink from said last-mentioned member, means for tripping saidprinting members, means directly actuated by said tripping means" forplacing said ink-removing means in inoperative position when theimpression is thrown off, and

for restoring said lnk-removmg' means means into operative positionbefore the impression is thrown on.

5. In a printing-press having a plurality of cooperating printingmembers, inking devices for one ofsaid members, means for removingsurplus ink from said last-mentioned member, means" for tripping saidprinting members, automatic means directly actuated by said trippingmeans for placing said ink-removing means in inoperaoif, and means forrestoring said ink-removing means into operative position before theimpression is thrown on.

6. In a printing-press having a plurality of cooperating printingmembers, inking devices for one of saidmembers, means for removingsurplus ink from said last-mentioned member, means for tripping saidprinting members, automatlc means d1- throwing off the impression, meansdirectly actuated by said throw-off means for breaking such contactsimultaneously with the impression throw-ofi, and means for restoringsuch contact before the impression is thrownon.

8. In a printing-press having two impression members to form a printingcouple, inking devices for one of said members, means contacting with:aid last-mentioned 'tive position when the impression is thrown rectlyactuated by said tripping means and member to remove surplus ink, meansfor throwing off the impression, automatic member surface, and means forallowing said scraper to lower into contact with said means directlyactuated by said throw-off surface before the printing relation of saidmeans for breaking such contact simulta neously with the impressionthrow-oil", and means for restoring such contact before the impressionis thrown on."

9. In a printing-press having two im-.

pression members to form a printing couple,

inking devices for .one of said members, means contacting with saidlast-mentioned member to remove surplus ink, means for throwin off theimpression, automatic means irectly' actuated by said throw-off meansand controlled by the stock, for

breaking such contact simultaneously with the impression throw-off, andmeans for re: storing such contact before the impression is thrown on. i

10. I n a printing-press having printing and impression members combinedwith means for separating said members at will, a scraper normallycontacting with the surface of said printing member, means di-' rectlyactuated by said member-separating means for raising said scraper fromsaid surface when said printing and impression members are separated,and means for allowing said scraper to lower to said surface before theprinting relation of said members isrestored. I 1

11. In 'a printing-press having printing and impression members combinedwith automatic means for separating said members, a scraper normallycontacting with the surface of-said printin member, means directlyactuated by sai member-separating means for raising said scraper fromsaid surface when said printing and impression members are separated,and means forallowing said scraper to lower to said surface before theprinting relation of said members isvrestored.

12. In a printing-press having printing and impression members combinedwith automatic means, controlled by the stock, for separatingsaidmembers, a scraper norma-lly contacting with the surface of saidprinting member, means directly actuated by said member, separatingmeans for raising'said scraper from said surface when said printingand'impression members are separated, and means for allowing saidscraper to lower to said surface before the printing relation of saidmembers is restored.

13. In a printing-press having printing and impression members combinedwith means for separating said members, a scraper normally contactingwith the surface of said printing member, means directly andsimultaneously actuated by said member separating means for raising saidscraper out of contact with said printingmembersis restored.

14. In a printing-press having printing and impression members combined,with automa ic means for separating said members, a scraper normallycontacting with the surface of said printing member, means directly andsimultaneously actuated by said member separating means for raising saidscraper out of contact with. said printingmember surface, and means forallowing said scraper to lower into contact with said surface before theprmting relation of said n members is restored.

15. In a printing-press having printing and impression members combinedwith automatic means, controlled by the stock, for separating saidmembers, a scraper normally contacting with the surface of said printingmember, means directly and simultaneously actuated by said memberseparating means for raising said scraper out of contact with saidprinting-member surface,

and means for allowing said scra'p'er to lower into contact with saidsurface before the printing relation of said members is restored.

16. In aprinting-press having a plurality of coiiperating printingmembers, inking devlces for one of said members, means for removingsurplus ink from said .last men-' tioned member, means for tripping saidprinting members, means directly actuated .by said tripping means forplacing said inkremoving means in inoperative position operating saidlast means, and devices under the control of the operator for alsooperat ing said means, said devices allowing said ink-removing means tobe moved into operative position before the rinting relation I of saidmembers is restore 17. vIn a printing-press having a plurality ofcoiiperating printing members, inking devices for one of said members,means for removing surplus ink from said last-mentioned member, meansfor tri ping said printing members, means dlrect y actuate by saidtripping means for placing said ink-removing means 1n inoperativeposition simultaneously with the stoppage of the printing operation,automatic devices, controlled by the stock, for operating said lastmeans, and devices under the control of the operator for also'operatingsaid means, said devices allowing said ink-removing means to be movedinto operative position before the printing relation of said members isrestored.

CARL G. PRITCHARD.

